• 멤브레인
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• 제29권5호
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• pp.246-251
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• 2019

올레핀/파라핀 분리를 위해 silver nanoparticle을 운반체로 이용하는 촉진수송막이 최근 많은 관심을 받고 있다. 기존 연구에서는 silver nanoparticle의 전구체로서 $AgBF_4$가 사용되어 왔다. 하지만 상대적으로 고가에 속하는 $AgBF_4$는 상업화에 적합하지 않기 때문에 비교적 저렴한 $AgClO_4$를 전구체로 이용해 제조된 silver nanopaticle를 활용해서 PEBAX-5513/AgNPs(전구체: $AgClO_4$)/7,7,8,8-tetracyanoquinodimethane (TCNQ) 복합막이 제조되었다. 그러나 여러 조성의 복합막이 제조되었으나 올레핀 분리성능은 관찰되지 않았다. FT-IR 분석 결과는 PEBAX-5513 고분자 내에서 silver nanoparticle이 형성되고 TCNQ에 의해 표면이 양극성화 되는 것을 확인하였지만 형성된 silver nanoparticle이 안정화 되지 못한 것으로 분석되었다. 이러한 결과들을 통해 은염 전구체의 음이온이 올레핀/파라핀 분리막에서 중요한 역할을 하는 것으로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.627-631
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• 1992

The dihydrido iridium(Ⅲ) complex [$Ir(PPh_3)_2H_2(ac)_2$]$BF_4$ (ac=acetone) reacts with 2-phenylpyridine and 7,8-benzoquinoline to yield the C-H activated complexes [$Ir(PPh_3)_2$H(ac)(L)]$BF_4$ (L= phenylpyridine; 7,8-benzoquioline). The dihydrido iridium(Ⅲ) complex [$Ir(PPh_3)_2H_2(ac)_2$]$BF_4$ also reacts with triaklysilane via an oxidative addition reaction to yield the trihydrido iridium complexes [$Ir(PPh_3)_2H_3SiR_3$]$BF_4$ (R =Et and Ph). The structual configuration was studied by conventional spectroscopy.

• Journal of Nutrition and Health
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• 제26권3호
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• pp.325-337
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• 1993

Korean breast-fed(BF) and formula-fed (FF) infants(n=31) were studied at their age of 1, 2 and 3 months to compare their intakes of energy, protein, lipid and lactose. Formulas had more energy, protein and lipid than breast milk, but the former had less lactose than the latter. The milk consumption of the FF infants was, however, greater than that of the BF infants with wide individual variation. As a result, the FF infants took in more energy, protein and lipid than the BF infants except lactose. The total daily caloric intakes(kcal/day) of the BF infants were 521.418 and 425 at their age of 1, 2 and 3 months respectively, and those of the FF infants were 676.752 and 723(at their age of 1, 2 and 3 months respectively). Daily protein intakes(g/days) of the BF infants were 9.5, 8.0 and 7.6 at their age of 1, 2 and 3 months respectively, and those of the FF infants were 13.9, 15.5 and 14.8(at their age of 1, 2 and 3 months respectively). The energy and protein of both the BF and the FF infants were deficient compared to the present Recommended Nutrient Allowances, and the deficiency of the BF infants was greater than that of the FF infants. But the energy intakes per kg of body weight of the FF infants at their age of 1 and 2 months were more than the present recommended energy allowances. And the protein intake per kg of body weight of the FF infant at the age of 1 month was the same as the present recommended protein allowances.

• 한국입자에어로졸학회지
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• 제7권1호
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• pp.9-19
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• 2011

The effects of different transient loading conditions on xylene removability and bacterial activity were evaluated in the polyurethane (PU) biofilter inoculated with Rhodococcus sp. EH831: BF1 (the control) was operated under continuous and constant loading ($200{\pm}50ppm$); BF2 under continuous and constant loading after a 2-week long-term shutdown; BF3 under discontinuous (8 h on/16 h off on weekdays and a 2 day-shutdown at weekends); and constant loading BF4 under discontinuous and high loading ($700{\pm}300ppm$); and BF5 under continuous and fluctuating loading (high loading for 8 h and low loading ($75{\pm}25ppm$) for 16 h on weekdays and low loading at weekends). Xylene removal efficiencies in the BF1, BF2, BF3, and BF5 were ranged 83-89%, indicating that 2-week long-term shutdown, intermittent or fluctuant loading condition did not significantly influence the biofilter performance. However, discontinuous and high load condition (BF4) caused to deteriorate xylene removability to 52%. Rhodococcus sp. EH831 could be maintained at $10^9{\sim}10^{10}CFU/g-dry$ PU under 5 kinds of loading conditions. The result of polymerase chain reaction-terminal-restriction fragment length polymorphism showed that there was no significant change in bacterial community structures by different loading conditions.

• 국제물리치료학회지
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• 제7권2호
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• pp.1037-1040
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• 2016

This study aims to investigate the effects of ankle foot orthosis(AFO) on the activities of tibialis anterior(TA), soleus(Sol), rectus femoris(RF) and biceps femoris(BF) during stairs descending. The activities of TA, Sol, RF and BF were initially measured while descending 4 stairs without using AFO. The activities of the same muscles were then measured again while descending 4 stairs while using AFO. Wilcoxon signed-rank tests were used to analyze the results in order to examine the differences between the with using AFO and without using AFO. Although the activities of TA, Sol and RF were relatively lower while using AFO than without using AFO, only the differences in Sol and RF activities were significant(p<0.05). The activity of BF was relatively higher while using AFO compared to the activity of BF observed without using AFO. However, difference was not significant(p>0.05). Conclusion of this study was observed since AFO's ground reaction force absorption during stairs descending reduced the need to use So and RF that is related to shock absorption. BF activity was increased with AFO than without during standing forward to correct the trunk stability.

• Journal of Nutrition and Health
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• 제31권3호
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• pp.305-314
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• 1998

Microflora in 14 breast-fed(BF) and 15 formula-fed(FF) infants were investigated before (2-3 months after birth) and after weaning (5-7 months birth) to find the floral differences between the two lactation groups and the floral changes after weaning. Bifidolbacteria showed the highest count among the species of microflora in the BF group before and after weaning, but in the FF group, streptococci showed the highest count before weaning and bifidobacteria after weaning. Before weaning , the count of bifidobacteria, lactobacilli and total acaerobes were significantly higher in the BF group than in the FF. However, the frequencies of clostridia and klesidella , along with the counts of streptococci and eubacteria, were higher in the FF group. After weaning , the only difference was that the total count of aerobic bacteria was higher in the BF group. The counts of streptococci in the BF group and lactobacilli and total anaerobes in the FF group after weaning were significantly higher than before weaning. However, the count of total aerobes in the FF group after weaning was significantly lower than the count before weaning.

• Natural Product Sciences
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• 제10권6호
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• pp.315-320
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• 2004

Alpha-viniferin was previously isolated as a cyclooxygenase (COX)-2 inhibitor from Carex humilis (Cyperaceae) and is an oligomeric stilbene compound with benzofuran (BF) moieties in its chemical structure. In the present study, a chemically synthetic BF compound, named as 3,3-dimethyl-2,3,4,6,7,8,9,10,11,12,13,14,15,16,17,18-hexadecahydro-1H-benzo[b] cyclopentadeca[d]furan-1-one, was discovered to inhibit bacterial lipo polysaccharide (LPS)-induced prostaglandin $E_2$ $(PGE_2)$ production in macrophages RAW 264.7. The BF compound exhibited a selectively preferred inhibitory effect on COX-2 activity over COX-1 activity. Furthermore, BF compound inhibited LPS-induced COX-2 expression at transcription level. As a down-regulatory mechanism of COX-2 expression shown by BF compound, suppression of nuclear factor $(NF)-{\kappa}B$ activation has been demonstrated. BF compound inhibited LPS-induced $NF-{\kappa}B$ transcriptional activity and nuclear translocation of $NF-{\kappa}B$ p65, in parallel, but did not affect LPS-induced degradation of inhibitory ${\kappa}B{\alpha}$ protein $(I{\kappa}B{\alpha})$. Taken together, anti-inflammatory effect of BF compound on $PGE_2$ production was ascribed by its down-regulatory action on LPS-induced COX-2 synthesis in addition to inhibitory action on enzyme activity of COX-2.

• 한국유기농업학회지
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• 제18권2호
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• pp.271-282
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• 2010

본 연구는 농축산 부산물을 이용한 환경친화적 유기액비의 제조와 시용 기술을 개발하여, 채소의 고품질 친환경 안전농산물 생산기술을 확립하고자 돈분뇨 처리과정에서 한외여과막을 통과하고 역삼투막에서 역류되어 나오는 농축액비에 부족한 성분을 부산물, 화학비료와의 혼합액비가 배추 생육과 수량, 토양에 미치는 영향을 검토하고자 수행하였다. 시험구는 대조구의 검정시비량를 기준으로 막분리 농축액비(CS)와 부산물액비구(BF), 막분리 농축액비(CS)와 부산물액비 혼합액비시용구(CS%+BF), 농축액비와 부산물액비 혼합에 질소를 보충한 유기-화학비료 혼합액비시용구(CS+BF+N), 대조구로 화학비료 추비시용구(CF) 등 5처리를 완전임의 3반복으로 배치하였다. 결과를 요약하면 다음과 같다. 1. 막분리 농축액비(CS)는 발효과정 중 pH의 변화가 적었으나 부산물액비는 발효초기 pH가 7.0 부근에서 호기발효 후 2일 부터 pH가 지속적으로 낮아져 발효 후 3일에서 7일 사이에 5.0 정도로 저하되었다가 발효 후 9일 부터 상승하여 발효 후 14일에 약산성에서 중성 부근에 도달하였다. 부산물액비의 EC는 발효 시작 시점에 8dS/m에서 발효와 함께 계속 상승하여 발효 종료시점인 30일에는 15dS/m로 도달하였다. 2. 막분리 농축액비(CS)는 질소함량은 $1,528mg/{\ell}$, 칼리함량은 $6,025mg/{\ell}$로 질소 함량에 비하여 칼리 함량이 4배나 높은 불균형적인 양분조성를 나타내었다. 그러나 부산물액비는 T-N 함량은 $1,760mg/{\ell}$, $K_2O$ 함량이 $1,921mg/{\ell}$로 질소와 칼리 성분의 균형이 맞아 추비용비료로 적합한 성분특성를 나타내었다. 3. 주당엽수는 대조구 58.7개에 비하여 유기액비-화학비료 맞춤액비 시용구(CF+BF+N)에서 65.0개로 높았으나 막분리 농축액비(CS)의 엽수는 49.2개로 매우 낮았다. 주중과 구중은 막분리 농축액비처리구에서는 불균형적인 양분조성으로 2.33, 1.82kg로 대조구의 3.29, 2.43kg보다 각각 29, 25% 감소되었다. 부산물액비(BF), 혼합액비 처리구(CS+BF)에서의 주중과 구중은 화학비료 대조구와 대등하였다. 맞춤액비시용구(CS+BF%+N)에서의 주중과 구중은 3.55, 2.68kg로 대조구보다 각각 8, 10% 높았다. 4. 배추식물체와 토양의 무기성분 함량은 막분리 농축액비(CS)처리구에서 $K_2O$ 함량은 높게 나타났다. 맞춤액비구는 T-N 함량이 다른 처리구 보다 높은 경향이었다.

• 한국가축번식학회지
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• 제10권1호
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• pp.19-26
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• 1986

This experiment was carried out to investigate the effect of bovine serum ablumin (BSA), sugars, glycerol equilibration time, straw size and thawing method on the survival index and the morphology of frozen boar spermatozoa. The results obtained were summarized as follow: 1. When the semen frozen in BF5 dilutor as pellet form was thawed in BTS at 37$^{\circ}$and 50$^{\circ}C$, BF5 dilutor with fructose showed higher sperm survival index than that with dextrose, however, when the semen was thawed on dry test tube at 37$^{\circ}C$, BF5 dilutor with sucrose showed higher sperm survival index than with other sugars. 2 When the semen forzen in BF5 dilutor with straw and thawed at 37$^{\circ}C$, BF5 dilutor with dextrose showed higher sperm survival index than those with other sugars, and there was no difference in sperm survival index between 0.5 and 1.0 ml straws. 3. The sperm survival index of frozen sperm was significantly (P<0.05) improved due to addition of BSA (0.05%) to BF5 dilutor. 4. When the extended semen with BF5 dilutor contatining 0.01 to 0.05% of BSA was frozen in the straw, the semen without glycerol equilibration showed significantly (P<0.05) higher sperm survival index than those with 2, 4 and 6 hrs glycerol equilibration time. 5. The sperm frozen in BF5 dilutor with dextrose or fructose, sucrose and raffinose showed 77 to 88% in normal acrosome rate and no difference among sugars. 6. The frozen semen showed lower normal acrosome rate than the first and second diluted semen, whereas the frozen semen showed higher swollen, damaged and missing acrosome rate than the first and second diluted semen. 7. Damaged and missing acrosome rate of sperm head due to freezing was somewhat inhibited by addition of BSA (0.01 to 0.05) to the BF5 dilutor.

• 상하수도학회지
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• 제35권4호
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• pp.277-284
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• 2021

The ballasted flocculation effects of the mill scale and magnetite on activated sludge were investigated. Both ballasted flocculants (BF) could remarkably improve the sludge settleability in terms of zone settling velocity (ZSV) and sludge volume index (SVI). With the BF dosage of 0.2 to 2.0 g-BF/g-SS, the magnetite particles showed better efficiency on improving settling behavior of activated sludge than the mill scale due to higher surface area and hydrophobic property. The efficiency of SVI₃₀ with magnetite injection was 2.5 to 11.3% higher than mill scale injection and that of the ZSV appreciated from 23.7% to 44.4% for magnetite injection. Averaged floc size of the BF sludge with magnetite dosage (0.5 g-BF/g-SS) was 2.3 times higher than that of the control sludge. Dewaterability of the sludge was also greatly improved by addition of the BF. The specific resistance to filtration (SRF) was reduced exponentially with increasing the dosage of BF. However, the BF's particle size effect on the SRF looks to be marginal. Consequently, for improving the dewaterability, the BF played a physical role to remove the pore water of the biological flocs by intrusive attachment and a chemical role to induce aggregation of the flocs by charge neutralization.